1.\" Copyright (c) 1990, 1991, 1993 2.\" The Regents of the University of California. All rights reserved. 3.\" 4.\" This code is derived from software contributed to Berkeley by 5.\" Chris Torek and the American National Standards Committee X3, 6.\" on Information Processing Systems. 7.\" 8.\" Redistribution and use in source and binary forms, with or without 9.\" modification, are permitted provided that the following conditions 10.\" are met: 11.\" 1. Redistributions of source code must retain the above copyright 12.\" notice, this list of conditions and the following disclaimer. 13.\" 2. Redistributions in binary form must reproduce the above copyright 14.\" notice, this list of conditions and the following disclaimer in the 15.\" documentation and/or other materials provided with the distribution. 16.\" 3. Neither the name of the University nor the names of its contributors 17.\" may be used to endorse or promote products derived from this software 18.\" without specific prior written permission. 19.\" 20.\" THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND 21.\" ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 22.\" IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 23.\" ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE 24.\" FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 25.\" DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 26.\" OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 27.\" HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 28.\" LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 29.\" OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 30.\" SUCH DAMAGE. 31.\" 32.\" from: @(#)strcpy.3 8.1 (Berkeley) 6/4/93 33.\" $NetBSD: strcpy.3,v 1.16 2003/09/08 17:54:33 wiz Exp $ 34.\" 35.Dd May 6, 2002 36.Dt STRCPY 3 37.Os 38.Sh NAME 39.Nm strcpy , 40.Nm strncpy 41.Nd copy strings 42.Sh LIBRARY 43.Lb libc 44.Sh SYNOPSIS 45.In string.h 46.Ft char * 47.Fn strcpy "char * restrict dst" "const char * restrict src" 48.Ft char * 49.Fn strncpy "char * restrict dst" "const char * restrict src" "size_t len" 50.Sh DESCRIPTION 51The 52.Fn strcpy 53and 54.Fn strncpy 55functions 56copy the string 57.Fa src 58to 59.Fa dst 60(including the terminating 61.Ql \e0 62character). 63.Pp 64The 65.Fn strncpy 66function copies not more than 67.Fa len 68characters into 69.Fa dst , 70appending 71.Ql \e0 72characters if 73.Fa src 74is less than 75.Fa len 76characters long, and 77.Em not 78terminating 79.Fa dst 80if 81.Fa src 82is 83.Fa len 84or more characters long. 85.Sh RETURN VALUES 86The 87.Fn strcpy 88and 89.Fn strncpy 90functions 91return 92.Fa dst . 93.Sh EXAMPLES 94The following sets 95.Dq Li chararray 96to 97.Dq Li abc\e0\e0\e0 . 98.Bd -literal -offset indent 99(void)strncpy(chararray, "abc", 6); 100.Ed 101.Pp 102The following sets 103.Dq Li chararray 104to 105.Dq Li abcdef 106and does 107.Em not 108null terminate 109.Va chararray 110because the source string is \*[Gt]= the length parameter. 111.Fn strncpy 112.Em only 113null terminates the destination string when the length of the source 114string is less than the length parameter. 115.Bd -literal -offset indent 116(void)strncpy(chararray, "abcdefgh", 6); 117.Ed 118.Pp 119The following copies as many characters from 120.Va input 121to 122.Va buf 123as will fit and null terminates the result. 124Because 125.Fn strncpy 126does 127.Em not 128guarantee to null terminate the string itself, we must do this by hand. 129.Bd -literal -offset indent 130char buf[BUFSIZ]; 131 132(void)strncpy(buf, input, sizeof(buf) - 1); 133buf[sizeof(buf) - 1] = '\e0'; 134.Ed 135.Pp 136Note that 137.Xr strlcpy 3 138is a better choice for this kind of operation. 139The equivalent using 140.Xr strlcpy 3 141is simply: 142.Bd -literal -offset indent 143(void)strlcpy(buf, input, sizeof(buf)); 144.Ed 145.Sh SEE ALSO 146.Xr bcopy 3 , 147.Xr memccpy 3 , 148.Xr memcpy 3 , 149.Xr memmove 3 , 150.Xr strlcpy 3 151.Sh STANDARDS 152The 153.Fn strcpy 154and 155.Fn strncpy 156functions 157conform to 158.St -isoC-99 . 159